Page 180 - Thomson, William Tyrrell-Theory of Vibration with Applications-Taylor _ Francis (2010)

Chap. 5 Problems 167

5-40 For the system shown in Fig. P5-40, IV^ = 200 lb and the absorber weight W2 = 50 lb.
If IF, is excited by a 2 lb-in. unbalance rotating at 1800 rpm, determine the proper
value of the absorber spring /c2

Figure P5-40.
5-41 In Prob. 5-40, if a dashpot c is introduced between IF, and IF2, determine the
amplitude equations by the complex algebra method.
5-42 A flywheel with moment of inertia / has a torsional absorber with moment of inertia
free to rotate on the shaft and connected to the flywheel by four springs of stiffness
k Ib/in., as shown in Fig. P5-42. Set up the differential equations of motion for the
system, and discuss the response of the system to an oscillatory torque.

Figure P5-42.

5-43 The bifilar-type pendulum shown in Fig. P5-43 is used as a centrifugal pendulum to
eliminate torsional oscillations. The U-shaped weight fits loosely and rolls on two pins

Figure P5-43.